IDENTIFICATION OF NEW GENES AND ANALYSIS OF THEIR EXPRESSION DURING LENS AND RETINA REGENERATION IN ADULT NEWTS

During lens regeneration in Pleurodeles waltl, the dorsal iris zone is the cell source of the-lens regeneration, while the ventral iris zone can serve as the cells' source of lens regeneration only under certai n experimental conditions. The method of subtractive hybridization was used for the identification of genes responsible for the different pr oliferative potential of these zones. Differential screening of the en riched cDNA libraries, which were obtained as a result of subtractive hybridization of the cDNA samples of the ventral and dorsal iris zones 14 days after lens removal, revealed four clones specific to the dors al iris and six clones specific to the ventral iris. Two of these, LeR -1 and VeR-1, were structurally characterized. Comparison of their pri mary structure with data from the Gene Bank showed no essential homolo gy with the known sequences. Time-related changes in LeR-1 and VeR-1 e xpression were shown during lens regeneration. LeR-1 and VeR-1 express ion was activated at the early stages of lens regeneration. The peaks of LeR-1 and VeR-1 expression were observed on the 14th day of lens re generation in the dorsal and ventral iris zones, respectively. Further more, LeR-1 is activated during retina regeneration. The results of So uthern hybridization suggest the presence of sequences complementary t o LeR-1 in the genomes of Pleurodeles waltl and Rana temporaria. We pr opose that the activation of LeR-1 expression is related to the trigge ring of lens regeneration, while the activation of VeR-1 expression ac companies the inhibition of proliferative activity in the ventral iris zone.